test(terminal): fix bench command output wait

scripts/terminal-bench.mjs

@@ -142,6 +142,7 @@ async function main() {
   const { chromium } = await importPlaywright();
   fs.mkdirSync(options.outputDir, { recursive: true });
 
+  console.error(`[terminal-bench] launching browser${browserLaunchLabel(options)}`);
   const browser = await chromium.launch(browserLaunchOptions(options));
   const results = [];
   try {
@@ -162,6 +163,9 @@ async function main() {
 }
 
 async function runScenario(browser, options, viewport) {
+  console.error(
+    `[terminal-bench] ${viewport.name}: starting ${options.lines} line output`,
+  );
   const context = await browser.newContext({
     viewport: { width: viewport.width, height: viewport.height },
     deviceScaleFactor: 1,
@@ -188,13 +192,16 @@ async function runScenario(browser, options, viewport) {
       requestAnimationFrame(sample);
     });
 
-    const command = `for i in $(seq 1 ${options.lines}); do printf 'bench-%05d abcdefghijklmnopqrstuvwxyz\\\\n' "$i"; done`;
+    const command = `for i in $(seq 1 ${options.lines}); do printf 'bench-%05d abcdefghijklmnopqrstuvwxyz\\n' "$i"; done`;
     const startedAt = performance.now();
     await page.locator(".terminal-screen").click();
-    await page.keyboard.type(command);
+    await page.keyboard.insertText(command);
     await page.keyboard.press("Enter");
-    await waitForBenchLine(page, options.lines, options.timeoutMs);
+    await waitForBenchLine(page, options.lines, options.timeoutMs, viewport.name);
     const elapsedMs = round(performance.now() - startedAt);
+    console.error(
+      `[terminal-bench] ${viewport.name}: output observed in ${elapsedMs}ms`,
+    );
 
     const probe = await page.evaluate(() => window.__terminalBench || {});
     frameSamples.push(
@@ -272,6 +279,16 @@ function browserLaunchOptions(options) {
   return {};
 }
 
+function browserLaunchLabel(options) {
+  if (options.browserChannel) {
+    return ` channel=${options.browserChannel}`;
+  }
+  if (options.browserExecutable) {
+    return ` executable=${options.browserExecutable}`;
+  }
+  return "";
+}
+
 export function pngSmokeFromBuffer(buffer) {
   const signature = buffer.subarray(0, 8).toString("hex");
   const isPng = signature === "89504e470d0a1a0a";
@@ -287,19 +304,50 @@ export function pngSmokeFromBuffer(buffer) {
   };
 }
 
-async function waitForBenchLine(page, lines, timeoutMs) {
+async function waitForBenchLine(page, lines, timeoutMs, viewportName) {
   const marker = `bench-${String(lines).padStart(5, "0")}`;
   const minHistoryRows = Math.max(1, lines - 200);
-  await page.waitForFunction(
+  const deadline = performance.now() + timeoutMs;
-    ({ text, minHistoryRows }) => {
+  let lastLogAt = 0;
-      const probe = window.__terminalBench || {};
+  let lastStatus = null;
-      return (
+
-        document.body.innerText.includes(text) ||
+  while (performance.now() < deadline) {
-        (probe.historyRows || 0) >= minHistoryRows
+    const status = await page.evaluate(
+      ({ text, minHistoryRows }) => {
+        const probe = window.__terminalBench || {};
+        const bodyText = document.body?.innerText || "";
+        const historyRows = Number(probe.historyRows || 0);
+        return {
+          matched: bodyText.includes(text) || historyRows >= minHistoryRows,
+          renderCount: Number(probe.renderCount || 0),
+          historyRows,
+          screenRows: Number(probe.screenRows || 0),
+          renderer: String(probe.renderer || ""),
+          mode: String(probe.mode || ""),
+        };
+      },
+      { text: marker, minHistoryRows },
+    );
+    lastStatus = status;
+    if (status.matched) {
+      return status;
+    }
+
+    if (performance.now() - lastLogAt >= 5000) {
+      console.error(
+        `[terminal-bench] ${viewportName}: waiting for ${marker}; ` +
+          `historyRows=${status.historyRows}/${minHistoryRows}, ` +
+          `screenRows=${status.screenRows}, renderCount=${status.renderCount}`,
       );
-    },
+      lastLogAt = performance.now();
-    { text: marker, minHistoryRows },
+    }
-    { timeout: timeoutMs },
+    await page.waitForTimeout(1000);
+  }
+
+  throw new Error(
+    `Timed out waiting for terminal output ${marker}. Last status: ${JSON.stringify(
+      lastStatus,
+    )}`,
   );
 }